Justice Sotomayor, who is from the Bronx and joined the court in 2009, has often spoken of her love for New York City. This year, she complained that ordering takeout was much slower in Washington than in New York, and said that she still jaywalked like a New Yorker.

She is one of four justices on the court from New York City. Each one grew up in a different borough: Justice Antonin Scalia in Queens, Justice Elena Kagan in Manhattan and Justice Ruth Bader Ginsburg in Brooklyn.

While it may be difficult to imagine Justice Scalia on the stage in Times Square, Justice Sotomayor has taken on a more public role as a justice, especially as she promoted her recent memoir, "My Beloved World." She has doled out career advice on "Sesame Street," appeared on "The Daily Show" and even salsa-danced with a Univision anchor.

The Rockettes and Lady Gaga led the countdown in Times Square the past two years. Before that, the duty fell to a wide range of people, from Bill and Hillary Clinton and Colin L. Powell to a group of local high school students.

Justice Sotomayor was selected because of her inspirational story of rising from a humble background to become the first Hispanic justice on the court, said Tim Tompkins, president of the Times Square Alliance. She has encouraged others to dream big, a nice message for a new year, he said.

"At its best, the new year is about pursuing dreams," Mr. Tompkins said on Sunday.

Anderson Cooper will host the televised party in Times Square, with performances by Miley Cyrus, Melissa Etheridge and others. Viewers should not expect to see Ms. Cyrus twerking near Justice Sotomayor. The justice will have a private space at the event, Mr. Tompkins said.

Mayor Michael R. Bloomberg will not attend the event for the first time in 11 years, organizers said. He has helped with the ball drop each year since he was elected, but he will celebrate privately with friends and family this year.